package com.dmz.flink;

import org.apache.flink.api.common.functions.FlatMapFunction;
import org.apache.flink.api.common.typeinfo.Types;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.streaming.api.datastream.DataStreamSource;
import org.apache.flink.streaming.api.datastream.KeyedStream;
import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.util.Collector;

import java.util.Arrays;

public class StreamWordCount2 {
    public static void main(String[] args) throws Exception {
        StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
        //DataSource<String> dataSource = batchEnv.readTextFile("E:\\IdeaProjects\\flinkTutorial\\src\\main\\resources\\hello.txt");
        DataStreamSource<String> dataStreamSource = env.readTextFile("E:\\IdeaProjects\\flinkTutorial\\src\\main\\resources\\hello.txt");

        // todo 转换数据格式
        SingleOutputStreamOperator<Tuple2<String, Long>> wordAndOne = dataStreamSource.flatMap((String line, Collector<String> words) -> {
            Arrays.stream(line.split(" ")).forEach(words::collect);
        }).returns(Types.STRING)
                .map(word -> Tuple2.of(word, 1L))
                .returns(Types.TUPLE(Types.STRING, Types.LONG));

        // todo 分组
        KeyedStream<Tuple2<String, Long>, String> keyedStream = wordAndOne.keyBy(t -> t.f0);

        // todo 求和
        SingleOutputStreamOperator<Tuple2<String, Long>> sum = keyedStream.sum(1);

        //  todo 打印
        sum.print();

        //  todo 提交
        env.execute();
    }
}
